func resourceAwsAutoscalingGroupUpdate(d *schema.ResourceData, meta interface{}) error {
	conn := meta.(*AWSClient).autoscalingconn

	opts := autoscaling.UpdateAutoScalingGroupInput{
		AutoScalingGroupName: aws.String(d.Id()),
	}

	if d.HasChange("desired_capacity") {
		opts.DesiredCapacity = aws.Long(int64(d.Get("desired_capacity").(int)))
	}

	if d.HasChange("launch_configuration") {
		opts.LaunchConfigurationName = aws.String(d.Get("launch_configuration").(string))
	}

	if d.HasChange("min_size") {
		opts.MinSize = aws.Long(int64(d.Get("min_size").(int)))
	}

	if d.HasChange("max_size") {
		opts.MaxSize = aws.Long(int64(d.Get("max_size").(int)))
	}

	if d.HasChange("health_check_grace_period") {
		opts.HealthCheckGracePeriod = aws.Long(int64(d.Get("health_check_grace_period").(int)))
	}

	if d.HasChange("health_check_type") {
		opts.HealthCheckGracePeriod = aws.Long(int64(d.Get("health_check_grace_period").(int)))
		opts.HealthCheckType = aws.String(d.Get("health_check_type").(string))
	}

	if err := setAutoscalingTags(conn, d); err != nil {
		return err
	} else {
		d.SetPartial("tag")
	}

	log.Printf("[DEBUG] AutoScaling Group update configuration: %#v", opts)
	_, err := conn.UpdateAutoScalingGroup(&opts)
	if err != nil {
		d.Partial(true)
		return fmt.Errorf("Error updating Autoscaling group: %s", err)
	}

	return resourceAwsAutoscalingGroupRead(d, meta)
}
func resourceAwsAutoscalingGroupUpdate(d *schema.ResourceData, meta interface{}) error {
	conn := meta.(*AWSClient).autoscalingconn

	opts := autoscaling.UpdateAutoScalingGroupInput{
		AutoScalingGroupName: aws.String(d.Id()),
	}

	if d.HasChange("default_cooldown") {
		opts.DefaultCooldown = aws.Long(int64(d.Get("default_cooldown").(int)))
	}

	if d.HasChange("desired_capacity") {
		opts.DesiredCapacity = aws.Long(int64(d.Get("desired_capacity").(int)))
	}

	if d.HasChange("launch_configuration") {
		opts.LaunchConfigurationName = aws.String(d.Get("launch_configuration").(string))
	}

	if d.HasChange("min_size") {
		opts.MinSize = aws.Long(int64(d.Get("min_size").(int)))
	}

	if d.HasChange("max_size") {
		opts.MaxSize = aws.Long(int64(d.Get("max_size").(int)))
	}

	if d.HasChange("health_check_grace_period") {
		opts.HealthCheckGracePeriod = aws.Long(int64(d.Get("health_check_grace_period").(int)))
	}

	if d.HasChange("health_check_type") {
		opts.HealthCheckGracePeriod = aws.Long(int64(d.Get("health_check_grace_period").(int)))
		opts.HealthCheckType = aws.String(d.Get("health_check_type").(string))
	}

	if err := setAutoscalingTags(conn, d); err != nil {
		return err
	} else {
		d.SetPartial("tag")
	}

	log.Printf("[DEBUG] AutoScaling Group update configuration: %#v", opts)
	_, err := conn.UpdateAutoScalingGroup(&opts)
	if err != nil {
		d.Partial(true)
		return fmt.Errorf("Error updating Autoscaling group: %s", err)
	}

	if d.HasChange("load_balancers") {

		o, n := d.GetChange("load_balancers")
		if o == nil {
			o = new(schema.Set)
		}
		if n == nil {
			n = new(schema.Set)
		}

		os := o.(*schema.Set)
		ns := n.(*schema.Set)
		remove := expandStringList(os.Difference(ns).List())
		add := expandStringList(ns.Difference(os).List())

		if len(remove) > 0 {
			_, err := conn.DetachLoadBalancers(&autoscaling.DetachLoadBalancersInput{
				AutoScalingGroupName: aws.String(d.Id()),
				LoadBalancerNames:    remove,
			})
			if err != nil {
				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
			}
		}

		if len(add) > 0 {
			_, err := conn.AttachLoadBalancers(&autoscaling.AttachLoadBalancersInput{
				AutoScalingGroupName: aws.String(d.Id()),
				LoadBalancerNames:    add,
			})
			if err != nil {
				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
			}
		}
	}

	return resourceAwsAutoscalingGroupRead(d, meta)
}
func resourceAwsAutoscalingGroupUpdate(d *schema.ResourceData, meta interface{}) error {
	conn := meta.(*AWSClient).autoscalingconn
	shouldWaitForCapacity := false

	opts := autoscaling.UpdateAutoScalingGroupInput{
		AutoScalingGroupName: aws.String(d.Id()),
	}

	if d.HasChange("default_cooldown") {
		opts.DefaultCooldown = aws.Int64(int64(d.Get("default_cooldown").(int)))
	}

	if d.HasChange("desired_capacity") {
		opts.DesiredCapacity = aws.Int64(int64(d.Get("desired_capacity").(int)))
		shouldWaitForCapacity = true
	}

	if d.HasChange("launch_configuration") {
		opts.LaunchConfigurationName = aws.String(d.Get("launch_configuration").(string))
	}

	if d.HasChange("min_size") {
		opts.MinSize = aws.Int64(int64(d.Get("min_size").(int)))
		shouldWaitForCapacity = true
	}

	if d.HasChange("max_size") {
		opts.MaxSize = aws.Int64(int64(d.Get("max_size").(int)))
	}

	if d.HasChange("health_check_grace_period") {
		opts.HealthCheckGracePeriod = aws.Int64(int64(d.Get("health_check_grace_period").(int)))
	}

	if d.HasChange("health_check_type") {
		opts.HealthCheckGracePeriod = aws.Int64(int64(d.Get("health_check_grace_period").(int)))
		opts.HealthCheckType = aws.String(d.Get("health_check_type").(string))
	}

	if d.HasChange("vpc_zone_identifier") {
		opts.VPCZoneIdentifier = expandVpcZoneIdentifiers(d.Get("vpc_zone_identifier").(*schema.Set).List())
	}

	if d.HasChange("availability_zones") {
		if v, ok := d.GetOk("availability_zones"); ok && v.(*schema.Set).Len() > 0 {
			opts.AvailabilityZones = expandStringList(v.(*schema.Set).List())
		}
	}

	if d.HasChange("placement_group") {
		opts.PlacementGroup = aws.String(d.Get("placement_group").(string))
	}

	if d.HasChange("termination_policies") {
		// If the termination policy is set to null, we need to explicitly set
		// it back to "Default", or the API won't reset it for us.
		if v, ok := d.GetOk("termination_policies"); ok && len(v.([]interface{})) > 0 {
			opts.TerminationPolicies = expandStringList(v.([]interface{}))
		} else {
			log.Printf("[DEBUG] Explictly setting null termination policy to 'Default'")
			opts.TerminationPolicies = aws.StringSlice([]string{"Default"})
		}
	}

	if err := setAutoscalingTags(conn, d); err != nil {
		return err
	} else {
		d.SetPartial("tag")
	}

	log.Printf("[DEBUG] AutoScaling Group update configuration: %#v", opts)
	_, err := conn.UpdateAutoScalingGroup(&opts)
	if err != nil {
		d.Partial(true)
		return fmt.Errorf("Error updating Autoscaling group: %s", err)
	}

	if d.HasChange("load_balancers") {

		o, n := d.GetChange("load_balancers")
		if o == nil {
			o = new(schema.Set)
		}
		if n == nil {
			n = new(schema.Set)
		}

		os := o.(*schema.Set)
		ns := n.(*schema.Set)
		remove := expandStringList(os.Difference(ns).List())
		add := expandStringList(ns.Difference(os).List())

		if len(remove) > 0 {
			_, err := conn.DetachLoadBalancers(&autoscaling.DetachLoadBalancersInput{
				AutoScalingGroupName: aws.String(d.Id()),
				LoadBalancerNames:    remove,
			})
			if err != nil {
				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
			}
		}

		if len(add) > 0 {
			_, err := conn.AttachLoadBalancers(&autoscaling.AttachLoadBalancersInput{
				AutoScalingGroupName: aws.String(d.Id()),
				LoadBalancerNames:    add,
			})
			if err != nil {
				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
			}
		}
	}

	if shouldWaitForCapacity {
		waitForASGCapacity(d, meta, capacitySatifiedUpdate)
	}

	if d.HasChange("enabled_metrics") {
		updateASGMetricsCollection(d, conn)
	}

	return resourceAwsAutoscalingGroupRead(d, meta)
}
func resourceAwsAutoscalingGroupCreate(d *schema.ResourceData, meta interface{}) error {
	conn := meta.(*AWSClient).autoscalingconn

	var asgName string
	if v, ok := d.GetOk("name"); ok {
		asgName = v.(string)
	} else {
		asgName = resource.PrefixedUniqueId("tf-asg-")
		d.Set("name", asgName)
	}

	createOpts := autoscaling.CreateAutoScalingGroupInput{
		AutoScalingGroupName:             aws.String(asgName),
		LaunchConfigurationName:          aws.String(d.Get("launch_configuration").(string)),
		NewInstancesProtectedFromScaleIn: aws.Bool(d.Get("protect_from_scale_in").(bool)),
	}
	updateOpts := autoscaling.UpdateAutoScalingGroupInput{
		AutoScalingGroupName: aws.String(asgName),
	}

	initialLifecycleHooks := d.Get("initial_lifecycle_hook").(*schema.Set).List()
	twoPhases := len(initialLifecycleHooks) > 0

	minSize := aws.Int64(int64(d.Get("min_size").(int)))
	maxSize := aws.Int64(int64(d.Get("max_size").(int)))

	if twoPhases {
		createOpts.MinSize = aws.Int64(int64(0))
		createOpts.MaxSize = aws.Int64(int64(0))

		updateOpts.MinSize = minSize
		updateOpts.MaxSize = maxSize

		if v, ok := d.GetOk("desired_capacity"); ok {
			updateOpts.DesiredCapacity = aws.Int64(int64(v.(int)))
		}
	} else {
		createOpts.MinSize = minSize
		createOpts.MaxSize = maxSize

		if v, ok := d.GetOk("desired_capacity"); ok {
			createOpts.DesiredCapacity = aws.Int64(int64(v.(int)))
		}
	}

	// Availability Zones are optional if VPC Zone Identifer(s) are specified
	if v, ok := d.GetOk("availability_zones"); ok && v.(*schema.Set).Len() > 0 {
		createOpts.AvailabilityZones = expandStringList(v.(*schema.Set).List())
	}

	if v, ok := d.GetOk("tag"); ok {
		createOpts.Tags = autoscalingTagsFromMap(
			setToMapByKey(v.(*schema.Set), "key"), d.Get("name").(string))
	}

	if v, ok := d.GetOk("default_cooldown"); ok {
		createOpts.DefaultCooldown = aws.Int64(int64(v.(int)))
	}

	if v, ok := d.GetOk("health_check_type"); ok && v.(string) != "" {
		createOpts.HealthCheckType = aws.String(v.(string))
	}

	if v, ok := d.GetOk("health_check_grace_period"); ok {
		createOpts.HealthCheckGracePeriod = aws.Int64(int64(v.(int)))
	}

	if v, ok := d.GetOk("placement_group"); ok {
		createOpts.PlacementGroup = aws.String(v.(string))
	}

	if v, ok := d.GetOk("load_balancers"); ok && v.(*schema.Set).Len() > 0 {
		createOpts.LoadBalancerNames = expandStringList(
			v.(*schema.Set).List())
	}

	if v, ok := d.GetOk("vpc_zone_identifier"); ok && v.(*schema.Set).Len() > 0 {
		createOpts.VPCZoneIdentifier = expandVpcZoneIdentifiers(v.(*schema.Set).List())
	}

	if v, ok := d.GetOk("termination_policies"); ok && len(v.([]interface{})) > 0 {
		createOpts.TerminationPolicies = expandStringList(v.([]interface{}))
	}

	if v, ok := d.GetOk("target_group_arns"); ok && len(v.(*schema.Set).List()) > 0 {
		createOpts.TargetGroupARNs = expandStringList(v.(*schema.Set).List())
	}

	log.Printf("[DEBUG] AutoScaling Group create configuration: %#v", createOpts)
	_, err := conn.CreateAutoScalingGroup(&createOpts)
	if err != nil {
		return fmt.Errorf("Error creating AutoScaling Group: %s", err)
	}

	d.SetId(d.Get("name").(string))
	log.Printf("[INFO] AutoScaling Group ID: %s", d.Id())

	if twoPhases {
		for _, hook := range generatePutLifecycleHookInputs(asgName, initialLifecycleHooks) {
			if err = resourceAwsAutoscalingLifecycleHookPutOp(conn, &hook); err != nil {
				return fmt.Errorf("Error creating initial lifecycle hooks: %s", err)
			}
		}

		_, err = conn.UpdateAutoScalingGroup(&updateOpts)
		if err != nil {
			return fmt.Errorf("Error setting AutoScaling Group initial capacity: %s", err)
		}
	}

	if err := waitForASGCapacity(d, meta, capacitySatisfiedCreate); err != nil {
		return err
	}

	if _, ok := d.GetOk("enabled_metrics"); ok {
		metricsErr := enableASGMetricsCollection(d, conn)
		if metricsErr != nil {
			return metricsErr
		}
	}

	return resourceAwsAutoscalingGroupRead(d, meta)
}
func resourceAwsAutoscalingGroupUpdate(d *schema.ResourceData, meta interface{}) error {
	conn := meta.(*AWSClient).autoscalingconn

	opts := autoscaling.UpdateAutoScalingGroupInput{
		AutoScalingGroupName: aws.String(d.Id()),
	}

	if d.HasChange("default_cooldown") {
		opts.DefaultCooldown = aws.Int64(int64(d.Get("default_cooldown").(int)))
	}

	if d.HasChange("desired_capacity") {
		opts.DesiredCapacity = aws.Int64(int64(d.Get("desired_capacity").(int)))
	}

	if d.HasChange("launch_configuration") {
		opts.LaunchConfigurationName = aws.String(d.Get("launch_configuration").(string))
	}

	if d.HasChange("min_size") {
		opts.MinSize = aws.Int64(int64(d.Get("min_size").(int)))
	}

	if d.HasChange("max_size") {
		opts.MaxSize = aws.Int64(int64(d.Get("max_size").(int)))
	}

	if d.HasChange("health_check_grace_period") {
		opts.HealthCheckGracePeriod = aws.Int64(int64(d.Get("health_check_grace_period").(int)))
	}

	if d.HasChange("health_check_type") {
		opts.HealthCheckGracePeriod = aws.Int64(int64(d.Get("health_check_grace_period").(int)))
		opts.HealthCheckType = aws.String(d.Get("health_check_type").(string))
	}

	if d.HasChange("vpc_zone_identifier") {
		opts.VPCZoneIdentifier = expandVpcZoneIdentifiers(d.Get("vpc_zone_identifier").(*schema.Set).List())
	}

	if d.HasChange("availability_zones") {
		if v, ok := d.GetOk("availability_zones"); ok && v.(*schema.Set).Len() > 0 {
			opts.AvailabilityZones = expandStringList(d.Get("availability_zones").(*schema.Set).List())
		}
	}

	if d.HasChange("placement_group") {
		opts.PlacementGroup = aws.String(d.Get("placement_group").(string))
	}

	if d.HasChange("termination_policies") {
		// If the termination policy is set to null, we need to explicitly set
		// it back to "Default", or the API won't reset it for us.
		// This means GetOk() will fail us on the zero check.
		v := d.Get("termination_policies")
		if len(v.([]interface{})) > 0 {
			opts.TerminationPolicies = expandStringList(v.([]interface{}))
		} else {
			// Policies is a slice of string pointers, so build one.
			// Maybe there's a better idiom for this?
			log.Printf("[DEBUG] Explictly setting null termination policy to 'Default'")
			pol := "Default"
			s := make([]*string, 1, 1)
			s[0] = &pol
			opts.TerminationPolicies = s
		}
	}

	if err := setAutoscalingTags(conn, d); err != nil {
		return err
	} else {
		d.SetPartial("tag")
	}

	log.Printf("[DEBUG] AutoScaling Group update configuration: %#v", opts)
	_, err := conn.UpdateAutoScalingGroup(&opts)
	if err != nil {
		d.Partial(true)
		return fmt.Errorf("Error updating Autoscaling group: %s", err)
	}

	if d.HasChange("load_balancers") {

		o, n := d.GetChange("load_balancers")
		if o == nil {
			o = new(schema.Set)
		}
		if n == nil {
			n = new(schema.Set)
		}

		os := o.(*schema.Set)
		ns := n.(*schema.Set)
		remove := expandStringList(os.Difference(ns).List())
		add := expandStringList(ns.Difference(os).List())

		if len(remove) > 0 {
			_, err := conn.DetachLoadBalancers(&autoscaling.DetachLoadBalancersInput{
				AutoScalingGroupName: aws.String(d.Id()),
				LoadBalancerNames:    remove,
			})
			if err != nil {
				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
			}
		}

		if len(add) > 0 {
			_, err := conn.AttachLoadBalancers(&autoscaling.AttachLoadBalancersInput{
				AutoScalingGroupName: aws.String(d.Id()),
				LoadBalancerNames:    add,
			})
			if err != nil {
				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
			}
		}
	}

	return resourceAwsAutoscalingGroupRead(d, meta)
}